Extended Theories of Gravity

By Salvatore Capozziello, M. De Laurentis. 2011

3,128 citations recorded by the source corpus.

Abstract Extended Theories of Gravity can be considered as a new paradigm to cure shortcomings of General Relativity at infrared and ultraviolet scales. They are an approach that, by preserving the undoubtedly positive results of Einstein’s theory, is aimed to address conceptual and experimental problems recently emerged in astrophysics, cosmology and High Energy Physics. In particular, the goal is to encompass, in a self-consistent scheme, problems like inflation, dark energy, dark matter, large scale structure and, first of all, to give at least an effective description of Quantum Gravity. We review the basic principles that any gravitational theory has to follow. The geometrical interpretation is discussed in a broad perspective in order to highlight the basic assumptions of General Relativity and its possible extensions in the general framework of gauge theories. Principles of such modifications are presented, focusing on specific classes of theories like f ( R ) -gravity and scalar–tensor gravity in the metric and Palatini approaches. The special role of torsion is also discussed. The conceptual features of these theories are fully explored and attention is paid to the issues of dynamical and conformal equivalence between them considering also the initial value problem. A number of viability criteria are presented considering the post-Newtonian and the post-Minkowskian limits. In particular, we discuss the problems of neutrino oscillations and gravitational waves in extended gravity. Finally, future perspectives of extended gravity are considered with possibility to go beyond a trial and error approach.

Subfields: Astronomy and Astrophysics

View Paper: https://www.semanticscholar.org/paper/6d778ff707018e779bb8162375a517df952121d8

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In Astronomy and Astrophysics

Citations in the corpus

Inflationary Cosmology in Modified Gravity Theories (2015, background): “, [10,11], whereas for dark energy and modified gravity, see, for example, References [12–20]).”
Dynamical behavior in f (T, TG) cosmology (2014, background): “The second direction that one can follow is to modify the gravitational sector itself (for a review see [3] and references therein), acquiring a modified cosmological dynamics.”
On the Evolution of the Hubble Constant with the SNe Ia Pantheon Sample and Baryon Acoustic Oscillations: A Feasibility Study for GRB-Cosmology in 2030 (2022, background): “The most natural extended framework is the f (R)-gravity proposal [162,163,167,381] which contains only an additional scalar degree of freedom.”